estrogen receptors in the adrenal cortex of the possum (trichosurus vulpecula).1. specific [3h]estradiol binding activity with characteristics of estrogen receptors was found in the cytosols and nuclear extracts of the adrenal cortex proper and special zone of the brushtail possum (trichosurus vulpecula). 2. the specific estradiol receptor had a sedimentation coefficient on sucrose gradients of approximately 9s and a molecular weight on gel filtration of more than 200,000. the adrenal cortex cytosol binds [3h]estradiol with high affinity (ka 5.5 x 10(9) m-1), and limited c ...19902361366
neurogenesis in a marsupial: the brush-tailed possum (trichosurus vulpecula). ii. sensorimotor pathways.the times of origin of neurons in sensorimotor pathways of the marsupial brush-tailed possum were determined with 3h-thymidine autoradiography. a series of 20 possums were injected with 3h-thymidine from postnatal days 5-95 and were normally allowed to survive until the brain cytoarchitecture was mature. brain stem and spinal sensorimotor regions were not labelled in our study and presumably form before birth in order to enable the newborn young to make the journey from the birth canal to the po ...19902245314
neurogenesis in a marsupial: the brush-tailed possum (trichosurus vulpecula). i. visual and auditory pathways.the times of origin of neurons in the visual and auditory systems were studied in a marsupial, the brush-tailed possum, using tritiated thymidine autoradiography. within the subcortical visual pathways, most neurons are generated between postnatal days 5 and 21, and the neurons of the primary visual cortex up to postnatal day 68. in the subcortical auditory pathways, most neurons are generated between postnatal days 5 and 28, and all auditory cortex neurons have appeared by postnatal day 46. neu ...19902245313
cholinesterase activity in sensory-nerve endings, capillaries and motor end plates of the facial skin of the brush-tailed possum (trichosurus vulpecula).the facial skin of two adult and one 50-day-old pouch animal of the marsupial mammal trichosurus vulpecula was removed after the animals has been suitably anesthetized and perfused for electron microscopy. small blocks of tissue (1 x 0.5 mm) were cut and incubated in acetylthiocholine iodide substrate for cholinesterase studies. the blocks were then subsequently postfixed in osmium tetroxide. thin sections were cut and stained with lead acetate. specific cholinesterase was found within the nerve ...19902075803
identification of 5 alpha-androstane-3 alpha,17 alpha-diol in adrenal venous plasma of female possum (trichosurus vulpecula).two hitherto unidentified c19 steroids were isolated from adrenal venous blood plasma of female possum (trichosurus vulpecula). they were 5 alpha-androstane-3 alpha,17 alpha-diol and its isomer 5 beta-androstane-3 alpha,17 alpha-diol. the compounds were isolated and identified by fractionation on paper chromatograms and hplc, followed by gas chromatography-mass spectrometry after conversion to trimethylsilyl ethers. in adrenal venous plasma the concentrations of the 5 alpha-isomer ranged from 24 ...19892724963
identification of 5 beta-pregnane and 5 beta-androstane derivatives in adrenal venous and peripheral blood plasma of the female possum (trichosurus vulpecula).in the possum a marked sex difference has been found in the steroids in adrenal venous plasma. four 5 beta-pregnane and four 5 alpha (beta) androstane derivatives together with ten 4-ene-3-keto steroids were isolated from the adrenal venous plasma of the female and definitively identified by gas chromatography-mass spectrometry. the major reduced steroids were: 5 beta-pregnane-3 alpha,17 alpha-diol-20-one and 5 beta-pregnane-3 alpha,17 alpha,20 alpha-triol, at concentrations of 52 +/- 12 microgr ...19892724960
changes in milk composition during lactation in the common brushtail possum, trichosurus vulpecula (marsupialia: phalangeridae).the milk constituents of trichosurus vulpecula, a folivorous marsupial, showed marked quantitative and qualitative changes during the course of lactation. the milk produced in the early stages of lactation was dilute, with about 9-13% (w/w) solids during the first 3 weeks, comprising mostly carbohydrate and protein (35-40%). at 20 weeks, about three-quarters of the way through lactation, the milk was much more concentrated, about 28% solids, with lipid the predominant fraction (30-35%), after a ...19892636424
intestinal lactase (beta-galactosidase) and other disaccharidase activities of suckling and adult common brushtail possums, trichosurus vulpecula (marsupialia:phalangeridae).small-intestinal disaccharidase activities of eight suckling t. vulpecula, aged from 34 to 150 days, and of two adult animals were investigated. intestinal maltase, isomaltase and sucrase activities increased with age, whereas lactase activities decreased. trehalase activities were relatively high in all animals and showed no obvious age-related changes. three separate beta-galactosidase activities, one neutral and two acid, acted on lactose. the neutral beta-galactosidase activity appeared to b ...19892517666
factors influencing prostatic 5 alpha-reductase activity in possum (trichosurus vulpecula).1. there were marked differences in prostatic wts among individual possums, but no evidence of a seasonally related change in wt could be established. it was concluded that the wt differences are mainly due to the changes in secretory activities. after castration the prostate wts fell while after administration of testosterone or oestradiol partially reversed this process. 2. seven steroid conversion products were isolated from prostatic homogenates incubated with [3h] testosterone; 5 alpha-andr ...19883356127
projection of cervical dorsal root fibers to the medulla oblongata in the brush-tailed possum, trichosurus vulpecula.this study describes the projection of cervical spinal afferent nerve fibers to the medulla in the brush-tailed possum, a marsupial mammal. after single dorsal roots (between c2 and t1) were cut in a series of animals, the fink-heimer method was used to demonstrate the projection fields of fibers entering the cns via specific dorsal roots. in the high cervical spinal cord, afferent fibers from each dorsal root form a discrete layer in the dorsal funiculus. the flattened laminae from upper cervic ...19873630955
effect of melatonin and removal of pouch young on the seasonality of births in the marsupial possum, trichosurus vulpecula.melatonin implants were placed in 5 adult female possums during december. births were observed from 31 march to 12 april in 4 control possums, and on 16 january, 1 and 6 february, 27 march and 27 april in the melatonin-treated animals. melatonin would appear to have advanced the start of the breeding season in 3 of the 5 animals. following removal of pouch young a subsequent birth is more likely to occur when young are removed early in the breeding season. these results would suggest that daylen ...19873598964
digestion and metabolism of high-tannin eucalyptus foliage by the brushtail possum (trichosurus vulpecula) (marsupialia: phalangeridae).the digestion and metabolism of eucalyptus melliodora foliage was studied in captive brushtail possums (trichosurus vulpecula). the foliage was low in nitrogen and silica but high in lignified fibre and phenolics compared with diets consumed by most other herbivores. the high lignin content was suggested as the main cause of the low digestibility of e. melliodora cell walls (24%); microscopic observations of plant fragments in the caecum and faeces revealed few bacteria attached to lignified tis ...19873571567
vulpecholic acid (1 alpha, 3 alpha, 7 alpha-trihydroxy-5 beta-cholan-24-oic acid): a novel bile acid of a marsupial, trichosurus vulpecula (lesson).a novel trihydroxylated c24 bile acid was isolated from the gallbladder bile of the australian opossum, trichosurus vulpecula (lesson). this acid, for which the name vulpecholic acid is proposed, was identified as 1 alpha, 3 alpha, 7 alpha-trihydroxy-5 beta-cholan-24-oic. the structure proof included mass spectral and 1h and 13c nuclear magnetic resonance characterization of all crucial derivatives obtained by: oxidation of the methyl ester to a triketone with the enolizable 1,3-diketone functio ...19873559398
evolution of mammalian x-chromosome inactivation: sex chromatin in monotremes and marsupials.the inactive mammalian x-chromosome is always late-replicating, and in eutherian mammals it is heterochromatic and hypermethylated. we propose that this multistep system has evolved from a more primitive system, remnants of which may be found in marsupials and monotremes. the heterochromatic x (sex-chromatin body) is a distinctive feature of interphase cells of certain tissues in eutherian females but not males. thus we have searched for a sex-specific chromatin body in these same tissues in mar ...19873453040
parasites and serological survey of the common brushtail possum (trichosurus vulpecula) from kangaroo island, south australia. 19863503151
weekly variations in body weight and plasma testosterone concentrations in the captive male possum, trichosurus vulpecula.the possum is a seasonally breeding marsupial which gives birth in queensland from march through to september. to ascertain whether this seasonality in breeding is manifest in the male reproductive system, body weight and plasma testosterone concentrations were examined in five possums. plasma testosterone concentrations fluctuated throughout the year and a seasonal cycle was observed, with a peak in testosterone concentration in march and a nadir in september. body weights fluctuated in a simil ...19863781210
effects of oestradiol, the oestrous cycle and pregnancy on weight, metabolism and cytosol receptors in the uterus of the brush-tail possum (trichosurus vulpecula).uterine weight, rna, dna, protein content, in-vitro rate of protein synthesis, cytosol oestrogen and progesterone receptors were examined after administration of oestradiol to ovariectomized animals and on days 0, 5, 9 and 13 of the non-pregnant cycle and day 13 of pregnancy. in ovariectomized animals, oestradiol increased uterine weight, rna:dna and protein:dna ratios and the concentration of cytosol receptors for oestradiol and progesterone. during the oestrous cycle there was a linear increas ...19863950527
epidermal langerhans cells in the opossum, trichosurus vulpecula. 200916031214
differences in steroid metabolism by testis, prostate and epididymis in the immature and adult possum (trichosurus vulpecula).immature possums 126-195 days old and adults over 1 year old were used. testicular homogenates from immature possums converted [3h]progesterone to nine different products, of which greater than 63% were 5 alpha-reduced androstane metabolites. the major product from adult testis was testosterone in yields greater than 60%. while metabolism of [3h]testosterone by the epididymis of immature possum was minimal, in adults 5 alpha-reduced products constituted greater than 80% of the yield. in contrast ...19863757486
structure of the uterine luminal epithelium of the brush-tailed possum (trichosurus vulpecula).morphology and morphometry of the luminal surface of the uterus of the brush-tailed possum were studied during the oestrous cycle, in anoestrous animals and after ovariectomy. at oestrus the secretory cells were small and the epithelium heavily ciliated. the relative surface area occupied by secretory cells reached a maximum on day 13 when plasma progesterone concentrations are maximal. the mean apical surface area of the secretory cells also reached a maximum at this time. both these measures d ...19854045824
peripheral androgen levels in the male brush-tail possum (trichosurus vulpecula).radioimmunoassays were established for the measurement of total androgens and the specific measurement of testosterone and 5 alpha-dihydrotestosterone in peripheral plasma of the brush-tail possum. androgen concentrations were measured in blood collected from indwelling jugular cannulae to determine whether the normal pattern of androgen secretion in this species was episodic and to attempt to relate total androgen and the pattern of testosterone secretion to the changes previously reported in p ...19853989424
identification of the major steroids in ovarian and adrenal venous plasma of the brush-tail possum (trichosurus vulpecula) and changes in the peripheral plasma levels of oestradiol and progesterone during the reproductive cycle.the quantitatively major steroid hormones in ovarian and adrenal venous plasma of the female brush-tail possum were identified by gas chromatography-mass spectrometry. the ovarian vein plasma samples all contained oestradiol and its concentration was highest during the pro-oestrous phase of the reproductive cycle. during this phase the concentration of progesterone was below the limit of detection but at day 13 of the oestrous cycle and pregnancy, the concentration of progesterone exceeded that ...19853989423
structure of the oviducal epithelium of the brush-tailed possum (trichosurus vulpecula).observations were made using scanning and transmission electron microscopy and were correlated with measurements of the mean surface area and the percentage area occupied by secretory cells to provide precise interpretation of the morphological data. in cyclic and anoestrous possums the oviducts were lined with elaborate folds of mucosa except in the portion of the isthmus adjacent to the uterus where the pattern was much simplified. the folds decreased in height and number after ovariectomy. se ...19854038518
some effects of breeding season and castration on the prostate and epididymis of the brushtail possum, trichosurus an attempt to understand the mechanism(s) responsible for the reported marked seasonal increase in prostatic, but not epididymal, weight in t. vulpecula, a number of parameters were measured in tissues from mature, entire males sampled within and outside of the breeding season and from castrates. conditions for the measurement of cytosol androgen receptors were also established. the weight of both the prostate and the epididymis was significantly elevated in the breeding season but the relati ...19852418813
differences in steroidogenesis by the subcellular fractions of adrenocortical special zone and cortex proper of the female possum (trichosurus vulpecula).steroidogenesis by subcellular fractions of adrenal cortex proper (c.p.) and special zone (s.z.) of female possum (trichosurus vulpecula) was studied. mitochondrial, microsomal and cytosol cell fractions were incubated with appropriate substrates in the presence of an nadph-generating system. the major products formed from [3h]progesterone and [3h]17 alpha-hydroxyprogesterone by the microsomal fraction of the c.p. were 11-deoxycortisol and 11-deoxycorticosterone and 3 alpha (beta)-hydroxy-5 alph ...19846597318
hypertrophied adrenocortical tissue of the australian brush-tailed possum (trichosurus vulpecula): uniformity during reproduction.adrenal glands from normal male and female brush-tailed possums (trichosurus vulpecula) were weighed and sectioned to investigate reported changes in the relative size of the hypertrophied region of the cortex during the reproductive cycle. total adrenal gland weight in normal females averaged 120 mg/kg body weight and the hypertrophied region occupied 40% of the gland volume. no significant variation was found in these figures between glands from pregnant, lactating and cyclic possums . in addi ...19846726106
factors influencing the release of noradrenaline from hypothalamic slices of the possum, trichosurus vulpecula.slices of hypothalamus of the possum, trichosurus vulpecula, were incubated with 3h noradrenaline and the subsequent spontaneous and k+-induced effluxes of 3h measured. unchanged 3h noradrenaline comprised virtually all the k+-induced efflux, indicating that there was little, if any, metabolism of the amine after its release. receptor-modulation of the k+-induced efflux of 3h was shown by inhibition of this efflux by noradrenaline, clonidine, angiotensin ii and leu-enkephalin, and by the increas ...19846497783
phagocytosis of sperm cytoplasmic droplets by a specialized region in the epididymis of the brushtailed possum, trichosurus vulpecula.during sperm maturation in the brushtailed possum, trichosurus vulpecula, cytoplasmic droplets are shed from maturing spermatozoa in the distal regions of the head of the epididymis. examination of luminal contents from various regions of the epididymis showed that the proportion of detached droplets in the luminal contents was reduced from about 45% in the proximal corpus epididymidis to less than 10% in the distal corpus and cauda epididymides. in contrast, the proportion of droplet-free sperm ...19846722242
primary visual cortex in the brushtailed possum: receptive field properties and corticocortical connections.the corticocortical connections and receptive field properties of primary or striate visual cortex of the brushtailed possum, trichosurus vulpecula, have been examined. in this australian marsupial species primary visual cortex has connections with four other visual areas in the occipital lobe. in these adjacent visual areas fibers from striate cortex terminate mainly in layers 3 and 4 and in some cases also in layers 1 and 2. in all four areas return connections to striate cortex originate pred ...19846093921
cell-mediated immunity in opossums (trichosurus vulpecula): the responses to purified protein derivative and an unrelated antigen. 198316030960
architecture of the basal region of the subcommissural organ in the brush-tailed possum (trichosurus vulpecula).the architecture of the basal region of the subcommissural organ (sco) and the subjacent neuropil was studied in the brush-tailed possum, trichosurus vulpecula (marsupialia). several structural features suggest that the basal mode of sco-secretion may be as prominent as the well-established apical secretion. some of the features that speak in favour of basal secretion are: (1) the existence of deep processes of secretion-laden sco cells which reach and surround the capillaries in the hypendyma a ...19836883462
neural elements associated with the subcommissural organ of the brush-tailed possum (trichosurus vulpecula).by means of various techniques and on the basis of a large sampling of the brush-tailed possum, trichosurus vulpecula, a detailed description is given of the morphology of the neural elements associated with the subcommissural organ (sco) and the leptomeninges on the dorsal surface of the midbrain. it is shown that the sco of the possum is richly innervated, the nerves reaching the cerebral aqueduct by passing through the organ; there is, however, no evidence of a neural link between the sco and ...19836640625
chronic fascioliasis in a brushtail possum (trichosurus vulpecula). 19827168725
reissner's fiber in the sacral cord and filum terminale of the possum trichosurus vulpecula: a light, scanning, and electron microscopic study.the ending of reissner's fiber (rf) and structural features associated with gaps or fissures in the rostral part of the filum were investigated using light, scanning, and transmission microscopic techniques in young and mature possums of both sexes. to the best of the author's knowledge the report contains results of the first successful application of the sem for a study of rf in the spinal cord. some new observations suggest that while the bulk of rf is formed by the subcommissural organ and m ...19827174881
failure to induce contact hypersensitivity in the opossum, trichosurus vulpecula. 198216030830
postnatal development of retinal projections in the brushtailed possum, trichosurus vulpecula.the postnatal development of retinal projections was studied in the brushtailed possum, trichosurus vulpecula. [3h]proline was injected into one eye of 13 young possums aged 24-84 days in order to trace retinal pathways. the dorsal lateral geniculate nucleus (lgnd) can be identified in nissl material at 19 days but not at 9-10 days. by 40 days some cytoarchitectural lamination of the lgnd is apparent and by 71 days the adult pattern of cell layers is present. at 24 days retinal fibers occupy by ...19826182955
auditory cortex in the marsupial possum trichosurus vulpecula.a microelectrode mapping survey was made of the auditory cortex of the acallosal marsupial possum trichosurus vulpecula. single unit and unit cluster responses, as well as evoked potentials, were obtained from 64 tangential, cortical penetrations. pontamine sky-blue marking of successful tracks aided in later reconstruction of tracks and identification of recording locations. only one auditory field was identified. the 98 units sampled in this field covered a wide range of best frequencies from ...19827096213
oestrogen receptors in the genital tract of the australian marsupial trichosurus vulpecula. 19827095404
interocular transfer in a marsupial: the brush-tailed possum (trichosurus vulpecula).the corpus callosum has been implicated as the major commissure mediating the interhemispheric transfer of visual information in placental mammals. as marsupials lack a corpus callosum, they may be incapable of such transfer. this study was undertaken to test this hypothesis. three brush-tailed possums (trichosurus vulpecula) underwent midsaggital transection of the optic chiasm to ensure that retinal input was restricted to the ipsilateral side of the brain. three other possums had sham operati ...19827159824
b lymphocytes in the australian brush-tailed opossum trichosurus vulpecula. 19826984399
the origin of mitotic sex-chromosome association in the brush-tailed possum, trichosurus vulpecula (marsupalia:phalangeridae).nonrandom associations between the sex chromosomes of the brush-tailed possum, trichosurus vulpecula, were found to be due to association of nucleolar organizer regions (nor's) on the x and y chromosomes. nor association was also observed between an autosome and the x chromosome. these findings, based on silver staining, are in contrast to the report of murray (1977), who observed sex-chromosome association in this animal and indicated that these nonrandom associations may reflect an association ...19826186438
the cranial endocast of the early miocene marsupial, wynyardia bassiana: an assessment of taxonomic relationships based upon comparisons with recent forms.wynyardia bassiana, a possum-like marsupial from the early miocene of tasmania has long been considered to display skeletal features intermediate between the relatively primitive polyprotodont and the advanced diprotodont marsupials. our examination of the latex endocast of the nearly intact neurocranium reveals that wynyardia's brain is clearly phalangeroid in external morphology, resembling closely that of the extant phalangerid, trichosurus vulpecula. these findings indicate that an unambigou ...19817326568
transneuronal transport of tritiated fucose and proline in the visual pathways of the brushtailed possum, trichosurus vulpecula. 19807443073
the development of the forebrain in trichosurus vulpecula. 19807254756
diurnal variation in plasma concentrations of testosterone, 5 alpha-dihydrotestosterone, and corticosteroids in the australian brush-tailed possum, trichosurus vulpecula (kerr). 19807189497
the ependyma of the saccular pineal gland in the non-eutherian mammal trichosurus vulpecula. a scanning electron microscopic study.the pineal gland in the possum is represented by a thickening in the wall of the pineal recess. a superficial pineal body and a pineal stalk are characteristically lacking. the ependyma related to the gland is specialized but differs markedly from the lining in other circumventricular organs in form and in surface morphology. two distinct topographic zones have been recognized. in the middle is a mass of cells which form a prominent knobby-surfaced central zone. these cells are characterized by ...19807448848
metabolism of alpha- and beta-pinene, p-cymene and 1,8-cineole in the brushtail possum, trichosurus vulpecula.1. the nature of the non-conjugated metabolites of the eucalyptus oil terpenoid components alpha-pinene, beta-pinene, p-cymene and 1,8-cineole in the urine and faeces of the brushtail possum was investigated. 2. alpha-pinene was metabolized to myrtenic acid and trans-verbenol, beta-pinene to myrtenic acid, p-cymene to p-cresol and cumic acid, and 1,8-cineole to p-cresol, 9-hydroxycineole and cineol-9-oic acid.19807385912
the organization of neocortical projections from the ventrolateral thalamic nucleus in the brush-tailed possum, trichosurus vulpecula, and the problem of motor and somatic sensory convergence within the mammalian brain.the retrograde transport of hrp was used to determine the extent and organizational details of the vl neocortical projection in trichosurus. the major, or external, part of vl projects homotypically to the anteromedial part of the parietofrontal cortex, overlapping the vp cortical projection field extensively, but not completely. overlap between the vl field and smi is most extensive in the area of rear limb representation, and decreases considerably in the area of the head representation. a sma ...1979536306
the subcommissural organ of the adult and pouch-young brush-tailed possum (trichosurus vulpecula). a scanning electron microscopic study. 1979509507
a scanning electron microscope study of the pineal recess of the adult brush-tailed possum (trichosurus vulpecula).the ventricular surface features of the pineal recess of 35 adult brush-tailed possums (trichosurus vulpecula) were studied, mainly with the scanning microscope. the complex and interesting details observed have not been reported before. the pineal recess shows three distinct zones, and it is suggested that these be called: central, paracentral, and peripheral. the surface cells of the central zone show neither cilia nor microvilli, the paracentral zone shows microvilli (in a polygonal and homog ...1979541240
observations on the secretions of the subcommissural organ and the pineal in the adult brush-talled possum (trichosurus vulpecula).secretory functions of the subcommissural organ (sco) were investigated using mainly transmission and scanning electron microscopes, in 40 adult (19 males, 21 females) trichosurus vulpecula which were caught in different seasons over several years. there is clear evidence of apical secretion, reissner's fiber (rf), a presumptive basal secretory material with associated perivascular space and labyrinthine basal lamina. secretory function does not appear to be related to the sex of the animal or t ...1979440531
ultrastructure of glomerulus in trichosurus vulpecula (possum). 1978755173
altered retinal projections in brushtailed possum, trichosurus vulpecula, following removal of one eye. 1978681552
prostatic function in the brush-tailed possum, trichosurus vulpecula. 1978690986
the effect of intravenous infusion of angiotensin ii on drinking in the australian marsupial trichosurus vulpecula.1. when marsupial brush-tailed possums were maintained on a normal fruit and vegetable diet with access to water ad libitum, i.v. infusion of synthetic angiotensin ii at rates of 0.035-3.5 mug/kg. min caused short-latency drinking in up to seven of eleven animals tested. these rates also had significant pressor effects.2. there was a positive correlation between the rate of angiotensin infusion and the percentage of tested animals which responded by drinking, as well as the amount of water drunk ...1978690940
the retinal origins of the optic nerve conduction latency groups in the brush-tailed possum, trichosurus vulpecula. 1978641235
an atlas of the dorsal thalamus of the marsupial brush-tailed possum, trichosurus several respects the dorsal thalamus of trichosurus presents a level of organizational complexity considerably in advance of that seen in didelphis. in particular, such features as the lamination of the dorsal lateral geniculate, the distinct subdivisions of the ventroposterior and lateroposterior complexes, and the more pronounced separation of the ventroanterior from the ventrolateral nucleus, are similar to conditions found in many eutherians. on the other hand, some features which trichos ...1978670061
the number and distribution of ganglion cells in the retina of the brush-tailed possum, trichosurus vulpecula.the distribution of ganglion cells in the retina of the adult brush-tailed possum was determined by light microscopy of nissl stained retinal whole mounts. qualitatively, the distribution in this marsupial retina shows features, such as an area centralis and a visual streak, which are found separately or together in eutherian mammals. the possum retina is avascular and the eye has a weak tapetum in the superior fundus.the retinal area is 260 mm2 and there are about 280,000 ganglion cells. the di ...1978624790
a study of steroid 11beta-hydroxylation by adrenal mitochondria of marsupials--part ii. the effect of corticotrophin, metopirone and ph on 11beta-hydroxylation of 11-deoxycortisol and 17alpha-oh-progesterone by adrenal mitochondria of possum (trichosurus vulpecula). 197824136
aspects of laterality in the marsupial trichosurus vulpecula (brush-tailed possum). 1977280202
morphology and histochemistry of the mandibular gland of the australian brush-tail possum trichosurus vulpecula (marsupialia).a histological, ultrastructural and histochemical study of the mandibular gland of the australian possum trichosurus vulpecula revealed essentially similar features as those described earlier for the mandibular gland of the taxonomically relatively unrelated american opossum didelphis. the secretory endpieces consist of a branched tubular part, composed of serous cells whose secretion granules contain neutral glycoproteins, and terminal acini, consisting of seromucous cells containing small amou ...1977900527
nonrandom sex-chromosome association and constitutive heterochromatin in the brush-tailed possum, trichosurus vulpecula (marsupialia: phalangeridae).nonrandom associations between the short arms of the sex chromosomes of six trichosurus vulpecula were studied in 455 cells from the spleen and bone marrow. the association occurs in both sexes and was found to be independent of age. there was, however, a significant difference in the degree of association between the two tissues studied. regions of constitutive heterochromatin were found to be located in the short arms of the x and y chromosomes by using a c-banding technique. nucleolar organiz ...1977862434
changes in steroid biosynthesis by adrenal homogenates of the possum (trichosurus vulpecula) at various stages of sexual maturation with special reference to 5 beta-reductase activity. 1977299622
the features of sperm maturation in the epididymis of a marsupial, the brushtailed possum trichosurus vulpecula.possum spermatozoa undergo a distinctive process of maturation in the epididymis, as shown by change in the properties of the sperm surface, by modification of their morphology and by their increasing capacity for progressive motility. modification of the sperm surface over the head and tail is demonstrated by the different affinities of sperm from successive regions of the epididymis for fitc-conjugated wheat germ agglutinin and concanavalin a, and for cationic ferric oxide colloidal particles. ...19761008039
spermiogenesis in the brush-tailed possum, trichosurus vulpecula (marsupialia). the development of the acrosome.acrosome development in the australian brush-tailed possum, trichosurus vulpecula, displays a number of extraordinary features. this is particularly evident in the later stages of spermiogenesis, when the area of the nuclear surface bounded by the nuclear ring, and covered by the acrosome, is reduced considerable. as a result, the acrosomal material becomes located over its definitive position on the anterior third of the dorsal nuclear surface; in this process it is thrown into a series of fold ...1976963736
ultrastructural changes in spermatozoa of the brush-tailed possum, trichosurus vulpecula (marsupialia), during epididymal transit. part ii: the acrosome.the acrosome in spermatozoa from the caput epididymidis of the australian brush-tailed possum, trichosurus vulpecula, typically forms a cup-like structure, sitting on the anterior third of the dorsal surface of the nucleus. the base of the acrosomal 'cup' is narrowly separated from the nuclear surface, while the body of the 'cup' projects voluminously away from the nucleus. during epididymal transit these pronounced marginal extensions of the acrosome are retracted towards the nucleus, and the e ...1976963735
proceedings: ultrastructure of the mid-piece of the spermatozoon in the marsupial, trichosurus vulpecula. 19761255593
effect of cortisol on utilization and hepatic release of glucose in the marsupial brush-tailed opossum, trichosurus vulpecula.brush-tailed opossums were prepared surgically with indwelling heatic and jugular venous catheters for blood sampling without disturbance in the conscious state. hepatic extraction of rose bengal was 21 +3 (s.d.) % and hepatic clearance, used as a measure of hepatic blood flow, was 42.5 +7 ml/kg/min. hepatic relaease of new glucose, calculated from the thorias vena caval-hepatic venous difference in glucose specific activity at equilibrium during i.v. infusion of [14c]glucose and hepatic blood f ...19761255041
corticosteroid binding by plasma proteins and the effects of oestrogens in the marsupial brush-tailed opossum, trichosurus vulpecula (kerr).using the techniques of equilibrium dialysis at 36 degrees c and gel filtration at 4 degrees c, a high-affinity, transcortin-like, corticosteroid binding system has been demonstrated in the blood plasma of the marsupial trichosurus vulpecula. the affinity constant for non-albumin binding was 4-018 +/- 1-032 x 10(7) (s.c.) 1/mol for males and 4-046 +/- 0.981 x 10(7) for females. the concentration of non-albumin binding sites was 1-82 +/- 0.76 x 10(-7) mol/1 in males and 1-86 +/- 0-57 x 10(-7) mol ...19761255062
spinocerebellar tracts in the brush-tailed possum, trichosurus vulpecula.the direct projections of the spinal cord onto the cerebellar cortex were traced using nauta method following the placement of cervical or thoracic spinal cord hemisections in six brush-tailed possums. degenerating fibres reached the cerebellum via typically placed dorsal and ventral spinocerebellar tracts. although complete differentiation of the terminations of ventral and dorsal tracts was not possible, it was found that the dorsal tract terminates mainly in the ipsilateral anterior lobe ermi ...1976990905
ultrastructural changes in spermatozoa of the brush-tailed possum, trichosurus vulpecula (marsupialia), during epididymal transit. part i: the flagellum.during epididymal transit, a fibre network and an array of vesicles develop in the posterior two-thirds of the midpiece in sperm of the brush-tailed possum, trichosurus vulpecula. the fibre network is developed by the time the sperm reach the corpus epididymidis, and is composed of evenly spaced, helically arranged fibres lying immediately beneath the plasma membrane. the angle of these fibrous helices is always counter to that of the underlying mitochondrial helix. separating the fibre network ...19751201595
uterine response to ovariectomy during the proliferative and luteal phases in the marsupial, trichosurus vulpecula.the uterine luteal phase in t. vulpecula is not dependent upon the secretions of the cl throughout its duration. ablation of the cl or ovariectomy after day 7 of the 26-day oestrous cycle does not result in the termination of the uterine secretory phase. the dependence of the luteal phase on the secretions of the cl is demonstrated by ablation of the cl or ovariectomy on days 2, 4, 8, 12 and 24 of the oestrous cycle. ablation of the cl before day 8 resulted in the inhibition of the impending lut ...19751167910
observations on the ultrastructure of a fiber network in the flagellum of sperm of the blush tailed phalanger, trichosurus vulpecula. 19751090744
steroid formation by the adrenal tissue of the possum (trichosurus vulpecula). 19751122716
effect of cortisol on insulin sensitivity of the marsupial brush-tailed opossum, trichosurus vulpecula (kerr). 19744452817
proceedings: the mediodorsal thalamic nucleus of the brush-tailed possum, trichosurus vulpecula. 19744615097
metabolic effects of cortisol and corticotrophins in the australian brush-tailed opossum, trichosurus vulpecula (kerr). 19744370736
proceedings: the spinocerebellar tracts of the brush-tailed possum (trichosurus vulpecula). 19734791416
proceedings: an ultrastructural study of degenerating spinal and cortical afferents in the inferior olivary nucleus of the brush-tailed possum (trichosurus vulpecula). 19734791412
development, function, and regression of the corpus luteum in the marsupial trichosurus vulpecula. 19734803466
pyramidal effects on some forelimb motoneurone populations of the arboreal brush-tailed possum (trichosurus vulpecula). 19734763622
inability to transmit breinlia sergenti to a marsupial, trichosurus vulpecula. 19734768723
adrenocortical function in the australian brush-tailed possum trichosurus vulpecula (kerr). 19734352942
cyclical changes in the uterine endometrium and peripheral plasma concentrations of progesterone in the marsupial trichosurus vulpecula. 19734803460
the effects of pyramidotomy on motor performance in the brush-tailed possum (trichosurus vulpecula). 19734698154
observations on the permeability properties of the egg membranes of the marsupial, trichosurus vulpecula. 19734700804
the acute toxicity of four common poisons to the opossum, trichosurus vulpecula. 19724519614
the leukocytes and platelets of a marsupial, trichosurus vulpecula. a comparative morphological, metrical and cytochemical study. 19724117142
the rubrospinal tract in a diprotodont marsupial (trichosurus vulpecula). 19725036035
corticobulbar projections of the marsupial phalanger (trichosurus vulpecula). ii. projections to the mesencephalon. 19725029132
pyramidal and extrapyramidal influences on some hindlimb motoneuron populations of the arboreal brush-tailed possum trichosurus vulpecula. 19725008719
the conducting system of the heart of a marsupial trichosurus vulpecula. 19724117470
the rubrospinal tract of the phalanger (trichosurus vulpecula). 19715147333
ascending pathways to the brain stem of the phalanger (trichosurus vulpecula). 19715147332
observations of the distribution of cholinesterases in the carotid body of the brush-tailed possum, trichosurus vulpecula. 19715147327
the role of the pyramidal tract in the production of cortically evoked movements in the brush-tailed possum(trichosurus vulpecula). 19715124461
corticobulbar projections of the marsupial phalanger (trichosurus vulpecula). i. projections to the pons and medulla oblongata. 19715566079
vestibular and somatosensory evoked centrifugal cutaneous nerve discharges in the decerebrate-decerebellate phalanger, trichosurus vulpecula. 19715567761
ovarian steroid secretion rates in the marsupial trichosurus vulpecula. 19715539106
observations on the permeability properties of the tertiary egg membranes of the marsupial trichosurus vulpecula. 19715539100
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